Wireless communications devices such as the BlackBerry® by Research in Motion Limited provide a variety of useful functions, such as voice communication, e-mail and Web browsing. These wireless devices typically include a full QWERTY-style keyboard or a reduced keypad to enable a user to enter alphanumeric text. In addition, either a trackball or a thumbwheel can be provided for scrolling or moving the cursor. Some new-generation devices incorporate touchscreen technology in which the user presses the screen with a finger, thumb or stylus. Touchscreen technology enables the display to present keys for data entry that are customized to the specific application or circumstances. However, one of main shortcomings of touchscreen technology is that they do not provide any tactile feedback to the user. In other words, the absence of any three-dimensional physically protruding keys makes the touchscreen prone to typing or onscreen selection errors. A solution proposed by the applicant is to employ shape-changing touch-sensitive display screens that have shape-changing zones that can be electrically (or possibly also magnetically) actuated to expand to form protruding keys. This technology is described in Applicant's U.S. patent application Ser. No. 11/760,390 entitled “Shape-Changing Display for a Handheld Electronic Device”. Shape-changing technologies and related techniques are described in a number of references, e.g. U.S. Pat. Nos. 6,287,485, 7,212,332, 5,739,946, and U.S. Pat. No. 6,894,677.
A general shortcoming of all modern handheld electronic devices, such as the ubiquitous wireless communications devices, is that the limited size of the display screen makes viewing difficult at times. Although most of these handheld devices include basic zoom functions for magnifying the image onscreen, these zoom functions magnify the entire image, thus resulting in an inevitable loss of context (due to the loss of information peripheral to the screen area being zoomed). Accordingly, techniques to selectively magnify an onscreen object (or to zoom in on a portion of the display) remain highly desirable, particularly in the context of the increasingly popular touchscreen devices.
It will be noted that throughout the appended drawings, like features are identified by like reference numerals.